Germanium negative-ion implantation into SiO2 layer on Si

► Photoluminescence of Ge-implanted SiO2 layer with various amount were studied. ► Germanium negative ions were used for the shallow implantation with a low energy. ► Two-stage annealing in N2 and in air was shown to be effective for PL. ► This annealing brought the stronger PL at 390 nm from 3.0 at.%-Ge samples.